Fluid clutch for use in automatic transmissions



L. E. WILHELMY FLUID CLUTCH FOR USE IN AUTOMATIC TRANSMISSTONS Filed Aug. 10, 1944 Sept. 16, 1947.

.LINCOLN WILHELMY /%////g Mgg ATToRNi-:Ys

Patented Sept. 16, 1947 FLUID CLUTCH FOR USE IN AUTOMATIC TRAN SMIS SION S Lincoln E. Wilhelmy, Manitowoc, Wis.

Application August 10, 1944, Serial No. 548,825

1 claim. 1

' This invention appertains to transmissions and more particularly to a novel speed changing power transmission particularly adopted for use between a prime mover, such as an internal combustion engine, and the work, such as the drive wheels of a motor Vehicle.

A salient object of my invention is the provision of a clutch embodying drive and driven members, with means for constantly operating the drive'member of the clutch from the engine and means for automatically operating the driven member of the clutch according to either the engine speed, in low gear, or the vehicle speed in the higher gears.

With this and other objects in View, the invention consists in the novel construction, arrangement, and formation of parts, as will be hereinafter more specifically described, claimed, and illustrated in the accompanying drawing, in which drawing the figure is a longitudinal sectional view through my improved variable speed transmission.

Referring to the drawing in detail, the letter T generally indicates my transmission and the same includes a drum I rigidly fastened to the fly wheel 2. The drum I and the fly wheel 2 form an inclosed housing which is filled with uid, such as oil. The ily wheel 2 is driven from the engine (not shown) in any preferred way.

Extending axially into the drum is the main drive shaft 3 and the forward end of the same is piloted, as at 4, into the axial center of the fly wheel for free rotation.

The drum I, itself, can be housed within a suitable casing 5Y and this casing also forms a support for the shaft 3, as will be later described. The shaft 3 extends into lthe gear casing 6 carried by the drum casing 5 and the rear end of the shaft 3 is piloted in the propeller shaft 1 for free rotation. This propeller shaft 1 drives the work, as can be readily understood. Bearings 8 are carried by the casing for rotatably supporting the propeller shaft 1. The gear casing E also supports a counter shaft v9.

' Rotatably mounted upon the main shaft 3 is a hollow drive shaft I 0 and bearings II can be placed between the shaft 3 and the hollow shaft I0. A second relatively short hollow shaft I2 is rotatably mounted relative to the shaft 3 and is disposed upon the shaft I0 for free rotation. Anti-friction bearings I3 are placed between the hollow shafts Ill and I2. It is to be noted that the shaft I0 extends beyond the shaft I2 and that these shafts can be provided with stuffing boxes I4,

TheY drive gear train for the transmission includes freely rotatable speed gears I5, I6 and II of the desired size and it is to be noted that the gear I 6 is operatively connected to the gear I5 by an over-running clutch I8 and that the gear Il is operatively connected to the gear I6 by an overrunning clutch I9. These gears l5, I6 and Il are in constant mesh, respectively, with gears 20, 2l, and 22. Ihe gears 20 and I5 in conjunction with gears I1 and 22 constitute the driving means for low speed, while the gears 2l and I5 in conjunction with gears I'I and 22 constitute the driving means for the intermediate or second speedl In third speed the drive is direct.

The gear 20 is keyed to the hollow shaft I2, while the gear 2I is keyed to the hollow shaft I0. Gear 22 is keyed directly to the main shaft 3.

Also arranged within the gear casing is the reverse mechanism, which includes a gear 24 keyed to or formed on a sleeve 25 carried by `the gear Il. This gear 24 meshes with an idler gear wheel 2B, which in turn, meshes with the reverse gear wheel 21 which is rotatably mounted directly on the propeller shaft 1. v

Feathered on the propeller shaft 'I is a manually actuated synchro-mesh unit 28 and this unit is adapted to be shifted into either operative engagement with gear 22 or the reverse gear 21 for operatively connecting either one of these gears withv the propeller shaft.

Mounted within the drum I are fluid clutch units 29, 30, and 3 I.

The clutch unit 29 includes a drive clutch section 32 which is feathered on the hub sleeve 33 of the drum. This hub sleeve is rotatably mounted on the hollow shaft I2 and suitable bearings 34 can be placed between the hub sleeve and the shaft I2. The lhub sleeve is also provided with a stuffing box. The casing 5 carries bearings 35 for rotatably supporting the hub sleeve and consequently this bearing also supports the hollow shafts I0 and I2 as well as a support for the main shaft 3. Facing the drive clutch section 32 is the driven clutch section 36 and these facing clutch sections are provided with any preferred type of buckets or vanes 32. The driven clutch section 36 is keyed directly to the hollow shaft I 2, A coil spring 3l of the desired tension is employed for normally urging the feathered drive clutch section 32 away from the driven clutch section 36. This clutch section 32 is movable toward the clutch section 36 against the tension of the spring 3l automatically, when a certain engine speed is reached by slidable governor weights 3B. Movement of the governor weights 38 by centrifugal force operates the push arms 39 through the medium of links 40. The push arms 39, at their outer ends, are pivoted to the drum and their inner ends engage the sliding clutch section 32.

When the engine speed is increased above its fast idle, the centrifugal force generated will throw the weights 38 outward, which will cause the cltch section 32 to be moved axially into the driven clutch section 36 giving a fluid clutch coupling causing the rotation of the hollow shaft I2. The turning of the shaft I2 drives the gear 20, which in turn, drives the gear I5. This gear I5 drives the gears I6 and I1 through the overrunning clutches I8 and I9. Gear I1, in turn, drives the gear 22 and this gear through the synchro-mesh unit 28 drives the propellerl shaft 1 and the vehicle will be moved ahead at low speed.

The second hydraulic fluid clutch 30 includes `a drive clutch section 4I and a driven clutch section 42. The drive clutch section 4I is secured directly to the drive drum I. The driven clutch section 42 is feathered on the-hollow shaft I0 and is normally urged away from the drive clutch section 4I by an expansion coil spring 43. The driven clutch section 42 feathered on hollow shaft I (I and driving clutch section 4I attached to drum I areeach provided with facing buckets or vanes 44. In order to move the clutch section 42 into driving relation with the clutch section 4I, sliding governor weights 45 are provided. When these governor weights 45 are thrown radially outward by centrifugal force the same actuate, through the medium of links 46, push arms 41. The outer ends of these push-arms are pivoted to the clutch section 42 and the inner ends of the arms bear against a pusher plate 48 secured to the hollow shaft I0.

It can be seen that when the vehicle is being driven at low speed that the hollow shaft I0 is also` driven through the Yintermeshing gears I6 and 2E. Consequently, the clutch section 42 is rotated with the hollow shaft I9. v

When sufficient speed is attained, the governor weights 45 are thrown outward by centrifugal force, which will move the clutch section 42 into driving position relative to the clutch section 4I. against the tension of the spring 43 and consequently the clutch section 42 will then be driven from the engine through the drum I and the clutch section 4l. Now, instead of the clutch section 42 being driven by the gear 2l, the same is driven from the clutch section 4 I as stated, and hence, gear 2| now rotates the gear I6. Gear I6 through the over-running clutch I9 drives the gear I1. but as the gear I6 is rotating faster than the gear I5, the over-running clutch I8 will be actuated in the opposite direction and hence no `movement will be imparted by the gear I6 to the gear I5. The meshing of the gear I1 with the gear 22 will drive the propeller shaft 1 through the synchro-mesh unit 28 and the vehicle will be in second speed.

The clutch unit 3| includes a drive clutch section 49 which is rigidly fastened to the drum I and a driven clutch section 50, both of which are provided with facing buckets or vanes 5I. The clutch section 5l] is feathered on the main shaft 3 for sliding movement and for driving the shaft. An expansion coil spring 52 is provided and normally holds the clutch section 50 out of driving relation with the clutch section 49. Slidably mounted upon the clutch section 50 are governor weights 53 and these governor weights are adapted to actuate, through the medium of links 54, push arms 55. The push arms 55 are pivoted to the clutch section 50 at their outer ends and their inner ends bear against a push plate 56 secured directly to the main shaft 3.

When the vehicle is in second speed and the engine is accelerated and obtains suiiicient driving speed, the governor weights 53 will be thrown outwardly, due to the fact that the shaft 3 is driven through the intermeshing gears 2| and I6 and I1 and 22. The movement of the governor weights 53 will push the clutch section 50 against the tension of the spring 52, into driving relation with the clutch section 49 and consequently the clutch section 49 will now drive the clutch section 59 and this clutch section 50 and its shaft 3 will be driven at a higher rate of speed by this direct drive than it is being driven by the second speed clutch through gears 2|, I6, I1, and 22. 4The propeller shaft 1 will now be directly driven from the main shaft 3 through the synchro-mesh unit 23 and consequently, the vehicle will be in high speed. The intermeshing of the gear 22 with the gear I1 will not drive the gear I6 in viewr of the overrunning clutch I9.

The same action above described, takes place in reverse, except that the reverse gear train 24, 26 and 21 is brought into play by the shifting of the synchro-mesh 28 into driving relation with the gear 21.

Other changes in details may be made without departing from the spirit or the scope of the claim, but what I claim as new is:

In a variable speed transmission mechanism; a fluid clutch including an engine driven drum having lfluid therein, a driven rotor clutch section vin said drum mounted for turning movement therewith and having vanes thereon, a rotary driven clutch rotor section in said drum having vanes thereon facing the vanes of the drive clutch section, one of said clutch sections being mounted for sliding movement toward and away from the other clutch section, one of said clutch sections having radially extending guideways therein, centrifugal weights .slidably mounted in said guideways for outward movement according to the speed of rotation of the drive clutch section, pivoted push levers actuated by said weights for moving the sliding clutch section toward the other clutch section, and spring means normally holding the sliding clutch section away from the other clutch section and the centrifugal weights at the inner ends of the guideways.

LINCOLN E. VVILHELMY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,102,378 Zeitler July 7, 1914 1,795,135 Molly Mar. 3, 1931 2,034,988 Nilsson et al. Mar. 24, 1936 2,055,895 Fawcett Sept. 29, 1936 2,150,151 Burrows Mar. 14, 1939 2,184,941 Maroto Dec. 26, 1939 2,189,537 Swennes Feb. 6, 1940 2,321,226 McKay June 8, 1943 2,359,930 lliller Oct. 10, 1944 2,363,952 Fillmore Nov. 28, 1944 

